Research in the area of behavioral medicine has demonstrated that Type A or coronary-prone-behavior is a risk factor for coronary heart disease (CHD). The clinical judgments involved in classifying individuals as Type A are based not only on verbal responses to structured interview (SI) questions and probing challenges, but also on nonverbal behavior during the interview. The proposed research is designed to improve clinical judgment of Type A behavior through systematic study of nonverbal behaviors--especially facial and body movements--which are indicators of Type A behavior, and of cardiovascular arousal, which has been proposed as the mechanism whereby Type A behavior exerts its CHD risk. Differences in nonverbal behavior between adult male Type As and Type Bs during video-taped SIs will be investigated, with emphasis on quantifying those nonverbal behaviors considered to be part of the Type A behavior pattern, as well as identifying any distinguishing nonverbal behaviors that have not yet been reported in the literature. The relationships between nonverbal behaviors and cardiovascular arousal during the SI will be examined for the SI as a whole and for critical segments within the SI. The indices of cardiovascular arousal will be blood pressure, measured before and after the SI, and heart rate, monitored throughout the SI. The findings on nonverbal behavior and cardiovascular arousal during the SI will be related to already available ratings of speech characteristics during the SI and measures of psychophysiologic reactivity to stress-induction tasks in the laboratory, which current research has indicated are also relevant to the Type A/Type B distinction. This research should provide in the long term a better understanding and more precise identification of the behavioral and physiological components of the Type A/Type B behavior pattern that would reduce the incidence of false positives (people rated as Type A but who do not develop CHD) and false negatives (people rated as Type B but who develop CHD) and would permit design of enhanced intervention strategies.